Loading unit



W. FONDILLER.

- LOADING UNIT. APPLICATION FILED SEPT. a. ma.

1,436,2Q4, Patented Nov. 211, 1922.

The windings of the cores are, however, so arranged that points 15 and 19 will be of opposlte polarities and points 16 and 20 will likewise be of opposite polarities, points 16 and 19 and likewise points 15 and 20 being of the same polarities so that there will be flux between the cores in one direction through the yoke 21, and a substantially equal flux in the opposite direction through the yoke 22. Under these circumstances, the mid-portions of the yokes will be at practically the same magnetic potential, that is, intermediate the potentials of the ends of the yokes, so that there will be sub stantially no magnetic flux through the bridge. The yokes 21 and 22 perform the same function as that performed by the yokes in the Olsson and Pleijel device, that is, by affording paths of low reluctance between the cores for the emergent flux, they materially add to the loading of the phantom circuit.

Current flowing in the physical circuit 5 will produce fluxes in the same direction in both halves of the core 11; but since the two cores are connected by the low reluctance yokes 21 and 22, and slnce these yokes must be wide enough to carry the phantom flux,

there is presented, between the adjacent ends of the two windings on the core, an appreciable area from which side circuit flux may pass from the core into the yokes. The. core 12 being of low reluctance, ofi'ers a path through which this emergent side circuit flux would, unless prevented, complete the portion of this circuit externally to the core 11. If the flux followed this path, cross-talk would be produced in the side circuit 6 i by reason of the currents induced by the interlinkage with the flux in the windings of the, core 12. The

bridge 24 prevents this by olfering a magnetic shunt through which the emergent side circuit flux is diverted from core 12,

for there is not, as is the case with the phantom flux, a corresponding balancing flux in the core 12 to equalize the magnetic potentials at the mid-points of the yokes.

Similarly, the side circuit .fiuxescaping from core 12 at 19 and 20 does not reach the core 11, but is shunted throughthe bridge 24. i

In order to avoid loss through eddy currents, the yokes 21 and 22 and the bridge 24 may be either laminated, in accordance with well-known practice, or formed of insulated particles of finely divided magnetic material, molded by pressure into the desired form.

In some instances it may be desirable to reduce the phantom circuit loading,-as

compared with the side circuit loading.

present invention by connecting the windthe other core, will be shunted through the bridge 24;, and so prevented from reaching the other core. In this case the crosssection and material of the bridge will be such as to increase its permanence sulficiently to enable it to carry the phantom current flux from both of the cores ofthe loadingunit. V v I As the ratio of phantom circuit loading to side circuit loading depends; upon the percentage of the flux thatis diverted through the bridge 24, that is, on the material and cross-section of the bridge, this invention affords a means for providing a loading unit in which this ratio has a value selected in accordance with the circumstances under which it is to be used.

What is claimed-is; i

1. A loading unit core structure ing two toroidal core members, means providing paths of low reluctance between said members, and alow reluctance shunt connecting said paths.

2. A loading unit core structure comprising two toroidal core members, and abridge of low reluctance forming a magnetic pat-h between diametrically opposite portionsof each of said core members. i

3. A loading unitcore structure comprisingtwo toroidal core members,-yokesof low reluctance between said members atdiametrically opposite points, and a bridgeof low reluctance connecting said yokes.

4. A loading unit core structure compris- 4 ingtwo toroidal core members, yokes of low reluctance between said members .atdiametrically opposite points, and a bridge of low reluctance connecting the mid-portions of said yokes.

'compris- 5. A loading unit-comprising two toroidal core members, windings. on each core on different sections thereof, yokes of low reluctance connecting said cores at points between said windings, anda bridge of low reluctance connecting said yokes. V 6. A loading unit core structure comprising two toroidal core members, and bridging means of low reluctance connecting said members at diametrically opposite points and also connecting said points of each member. 7. A loading unit adapted .for use with two physical circuits and a derived phantom circuit comprising two circumferentially complete core members, one for each'physi cal circuit, means providing for the passage from each of sa1d cores to the other of flux due to current in the phantom circuit, and

means for divertingfrom each core flux from the other core due to the current in the physical circuit with which it is associated.

8.,A loading unit adapted for use with two physical circuits and aderived phantom circuit comprising two circumferentially complete core members, one for each physical circuit, means providing magnetic paths between said core members, and a magnetic shunt connecting said paths.

9. A device for magnetically connecting a pair of circumferentially complete loading unit cores comprising, in addition to said pairs of cores, two core-connecting members and a third member connecting said coreconnecting members.

10. A loading unit core structure comprising two circumferentially complete core members, yokes of low reluctance between said members at diametrically opposite points, and a bridge of low reluctance connecting said yokes.

11. A loading unit core structure comprising two circumferentially complete core members and bridging means of low reluctance connecting said members at diametrically opposite points and also connecting said points of each member.

12. A loading unit adapted for use with two physical circuits and a derived phantom circuit comprising two core members, each one forming the major portion or a magnetic circuit for its physical circuit, means providing magnetic paths between said core members, and a magnetic shunt connecting said paths.

13. A loading unit adapted for use with two physical circuits and a derived phantom circuit comprising a pair of core members for each physical circuit, means providing for the passage from each of said pairs to the other pair of flux due to current in the phantom circuit, and additional means for diverting from each pair'fiux from the other pair due to current in the physical circuit with which it is associated.

In witness whereof, I hereunto subscribe my name this 28th day of August, A. D. 1918.

WILLIAM FONDILLER. 

